The present invention relates generally to heat shrink tools and more particularly to a device for accurate assembly of a tool to a tool holder by the heat shrink method.
Connecting a tool to a tool holder by the heat shrink method is a well-known process. An example of the general process is described in U.S. Pat. No. 5,311,654 issued to Harold D. Cook on May 17, 1994. The heat shrink process is typically used with a tool holder having a bore for receipt of a tool having a shank. The tool holder is heated to expand the tool holder bore. The shank of the tool is then inserted into the bore. As the tool holder cools, the bore shrinks around the shank holding the shank within the tool holder.
The heat shrink method is an effective method for connecting a tool to a tool holder. However, in most applications, the tool must be precisely mounted within the tool holder or the tool holder cannot be used. It should be appreciated that these tools are typically used in operations that require very precise alignment and positioning. Slight variations in the alignment between tool and tool holder results in the production of defective parts. One of the major disadvantages of known methods for connecting a tool to a tool holder using the heat shrink method is the need to measure each tool and tool holder and the inaccuracy that can result from these repetitive measuring operations. Human error is a significant factor. A worker must measure the tool length and the tool holder length and then adjust the position of the tool to get the appropriate overall length. To reduce human error somewhat, another method employs a pre-qualified measuring rod to determine the appropriate depth of the tool within the tool holder. When this rod wears, the positioning is wrong and resultant tools and tool holders cannot be used. Furthermore, the heat shrink process must be done quickly to avoid down time when changing tools. If the heat shrink method is slow, tool changes will be slow resulting in the overall slowing of the entire operation in which the tool and tool holder are being used.
Accordingly, it would be advantageous to provide a tool assembly unit for rapidly and precisely connecting a tool to a tool holder.
It is an object of the present invention to provide a tool assembly unit for coupling a tool and a tool holder. The unit includes a measuring device adapted to determine the position of the tool with respect to the tool holder, an alignment device coupled to the measuring device and being adapted to receive the tool holder, a moveable rod slideably disposed on the alignment device and coupled to the tool, with the rod being adapted to move the tool with respect to the tool holder to a desired position as measured by the measuring device.
It is another object of the present invention to provide a tool assembly unit for coupling a tool and a tool holder by heat shrinking. The unit includes a measuring device adapted to determine the position of the tool with respect to the tool holder, an alignment device coupled to the measuring device and being adapted to receive the tool holder, a heating device slideably mounted on the alignment device and defining a bore for sliding a tool therethrough with the heating device adapted to be removably mounted on the tool holder for heating the tool holder, a moveable rod slideably disposed on the alignment device and being adapted to be coupled to the tool, with the rod being further adapted to move the tool with respect to the tool holder to a desired position as measured by the measuring device.
It is still another object of the present invention to provide a method for coupling a tool with a tool holder using a tool assembly unit including a measuring device coupled to an alignment device and a moveable rod slideably disposed on the alignment device. The method includes the steps of mounting the tool holder on the alignment device, coupling the moveable rod to the tool, measuring an actual relative position between the tool and tool holder, moving the tool within the tool holder until the actual relative position of the tool relative to the tool holder is equal to a desired position, and removing the tool holder and the tool from the alignment device.
It is still another object of the present invention to provide a method for coupling a tool with a tool holder by heat shrinking using a tool assembly unit including a measuring device coupled to an alignment device having a heating device slideably mounted thereon and a moveable rod slideably disposed on the alignment device. The method includes the steps of mounting the tool holder on the alignment device, heating the tool holder, coupling the moveable rod to the tool, measuring an actual relative position between the tool and the tool holder, moving the tool within the tool holder until the actual position of the tool relative to the tool holder is equal to a desired position, shrinking the tool holder around the tool, and removing the tool holder and the tool from the alignment device.
The subject invention provides many advantages over conventional tool assembly units by providing a tool assembly unit that rapidly and precisely couples a tool and a tool holder. One of the major advantages is reducing or eliminating the need to measure each tool and tool holder, thereby significantly reducing the inaccuracy that can result from these repetitive measuring operations due to human error. Another advantage is that rod wear does not result in improper positioning of the tool relative to the tool holder, thereby reducing cost by reducing the number of resultant tool assembly units that cannot be used. Furthermore, the tool assembly unit of the present invention permits the heat shrink process to be done quickly to avoid down time when changing tools, thus reducing tool change time and encouraging an efficient assembly operation.